Work center



M. ALDEN WORK CENTER Nov. 18, 1958 5 Sheets-Sheet 1 Filed June 22, 1954Filed June 22, 1954 M. ALDEN 2,860,404

WORK CENTER 5 Sheets-Sheet 2 2 .8 ,INVEVNTOR G6 fl/z/fokA/r/ /z BY a:\G7 69 b7 ATTORNEYS M. ALDEN Nov. 18, 1958 WORK CENTER 5 Sheets-Sheet 3Filed June 22, 1954 ATTORNEYS v Nov. 18, 1958 M. ALDEN 2,860,404

WORK CENTER I Filed June 22, 1954 5 Sheets-Sheet 4 INVENTOR M175) A/rkzzATTORNE 3 M. ALDEN WORK CENTER Nov. 18, 1958 5 Sheets-Sheet 5 Filed June22, 1954 km M R/ W mA M N 7 R I M M YW United States Patent WORK CENTERMilton Alden, Wellesley, Mass.

Application June 22,.1954,.Serial No. 438,451

Claims. (Cl. 29-200) Although, the advantages of logical. and systematiclayout of production lines and planning have long been recognized andused in mass production industries such as. automobile and electricalappliance manufacturers, the. time and money-saving techniques developedby these industries have not been adaptable to light manufacture of arelatively small number of articles because of the time, cost andinflexibility of a conventional production line.

Itis therefore the objects of this invention to provide a productionsystem which permits a production line to be set up and removed quicklyand easily, which permits a logical layout of work stations or centers,which requires a minimum of floor space, which is attractive inappearance, which increases the productivity of the workers whichfacilitates the installation of small tools and fixtures, which, permitsthe various services to be. con-- nected and disconnected readily, whichprovides means for transporting the articles being manufactured. betweenwork centers, which provides means of storing of components andinventory control at the various work, centers, and which advances themanufacturing arts generally.

According to my present invention: the production system comprises aplurality of work stations or centers which are a standard. size insofaras each center has a similar sized work top or pallet. The pallets are.ofconsiderably smaller size than has been. previously thought possible.by using containers which. store the pieces or components required bythe operator in a container located. in. a generally vertical planerather thanin bins or tote boxes fanned. out around the operator as isusually done. Further saving in the space required isobtained bygrouping all the services required in a generally vertical enclosure orhousing running along the back of a framework. which supports a row ofpallets forming the work surfaces for the work centers. On each palletis permanently mounted the tools and fixtures. and component containersrequired. to perform the operation of the particular work center. Thepallets are made as cheaply as possible, for example, .of wood cores,covered with masonite so that mounting holes, cut-outs, or otheralterations necessary can be made to accommodate the fixtures and tools,The low cost of the pallets also makes it'possible to leave the toolsand fixtures permanently attached so that whenever a run on a particulararticle or device is completed and the operations performed at one ormore of thecenters are temporarily no longer required, the pallet and,attached tools and fixtures are removed and stored as a unit until theoperations they are arranged to perform are again needed. To facilitatesuch changeover the pallets. are arranged to be readily removedfromtheir supporting frame and the connections to the services are made byelectrical plugs, flexible hoses and quick disconnect joints. Tofacilitate the movement of components and partiallycompleted articlesfrom one Work center to another, a belt conveyor is located adjacenteither the front or back of the pallets.

2,860,404 Patented Nov. 18, 195.8

The conveyor support or frame is preferably made, up. of a plurality orinterconnecting elements each having, a length which is equal to the.width of a pallet,v the cross section of the frame being I-shaped with ahorizontally disposed web upon either side of which the belt is carried.

These and other objects and aspects of the. invention will be. apparentfrom the. following; description of, aspecific embodiment. of the.invention which refers to drawings wherein:

Fig, l is anisometric view of four adjacent, workcenteIs;

Fig. 2 is an isometric view of two work centers show.- ing one palletpartially removed;

Fig. 3. is anisometric view of the supporting framefor the. work centersshown. in Fig. 1;;

Fig. 4 is a section; view on line. 4-4 of. Fig. 3;;

Fig. Sis a sectional view on line. 5-5. of Fig. 4;

Fig. 6 isa rear isometric view of. a. supporting frame with a section.of the duct for the services removed;

Fig. 7. is an isometric view of the belt conveyor;

Fig. 8. is an explodedv isometric view of two. frame sections;

Fig. 9. is. an enlarged. fragmentary view showing the ramps for loadingand. unloading the conveyor;

Fig. 10 is. an. isometric view ofa container or hopper for. components;

Fig. 11 is anexploded isometric view. of the container;

Fig. 12 is anisometric view of a. foot for the container;

Fig, 13. is, an isometric view showing the arrangement of severalcontainers on a pallet; and

Fig. 1.4. is a. diagrammatic. view showing the. manner in which the.containers are, stored and distributed.

A preferred. embodiment of the. invention shown in Fig, I. comprises asupporting frame. 2.0..upon which are c rr ed removable work. tops, suchas. the wooden pallets 22, to; form a. continuous. table. or benchhavinga back wall which. is. a hollow vertical, enclosure. such as theduct. 24"., Within the. duct.2.4are carried the lines. for services suchas electricity, compressed air, gas,.and exhaust as are required. forthe various, manufacturing operations. The. duct 24 also. acts, as.ananchor for stanchions 26 for florescent lamp fixtures28.

Each of. the'Pall'ets. 22. forms. a station or work center where oneparticular manufacturingor assembling operation is. carried. on,Accordingly, the. first station on. the left of Fig.1 is provided. withan arbor press 30 which is bolted. to its pallet, 22. A. work center atwhich slow or complicated. operations. are performed requiring. a longertime to complete 1118 .35, if. necessary, be duplicated at one or morestations. such as. the second. work center where there is. also,mounted. an arbor press. 30. At. the third station is locatedv an air,operated press 32which is connected to a, compressed air line (notshown). within the duct, 24 by means of a flexible hose 3.4. as.will.be-. de-

scribed later. The. fourthstation is provided. with a fly press 36.- anda vertical container or. hopper 3.8 for components which will; bedescribed indetail hereinafter...

Transportation of the. partially completed devices. or

articles of manufacture (not shown), between. different work centers isaccomplished by a. belt conveyor-40,- located either abutting. the frontedges. of the pallets. 22, as

shown in, Fig. 1, or, alternatively, on the top of the pallets, adjacentthe service; duct 24 at the rear of the, work center. The. conveyor 40,.which is. described inv detail the outlets 46 in the service duct 24...The flexible lead to the fluorescent lamps 28 is also plugged intoanother of the outlets 46'. Any electricalpower required in the"manufacturing operations either for motors, soldering irons, or heatingunits is similarly obtained from electrical busses located in theservice duct 24.

Although only four stations or work centers are shown in Fig. 1, it willbe evident that my invention is not so limited and that the maximumnumber of centers in one row need be limited only by the space availablein the work room or the number of operations required in the productionlines. When more centers are needed than can be accommodated by thelongest dimension of the work room more than one row of centers is used.Con versely, less than four stations may be used, as is illustrated inFig. 2, it having been found that support frames 20 with only two orthree work centers and provided with bare pallets are ideally suited forlaboratory benches because of the convenient location of the variousservices in the rear duct 24.

Fig. 2 also serves to illustrate the manner in which a pallet 22 may besimply slid from the supporting frame 20 without the necessity ofremoving the attached tool 48. This feature permits great flexibilitybecause of the ease with which the operation at any station can bechanged so that many of the benefits and advantages of productiontechniques can be realized by small shops which ordinarily could notaflord the time and money to set up a conventional production line tomanufacture items with a limited production. Once the elements of thesupport frames 20 are bolted together in place, a production line is setup for any particular item by securing the necessary tools, fixtures andcomponent containers 38 required for each step to the top of a pallet 22either while the pallet is in place in the frame22 or in a separateassembly area or room. The various service connections are made to thebusses and lines in the service duct 24 by extension cords and flexiblehoses so that the skill and time required is reduced to a minimum.

While planning is, of course, required, it can be kept to a minimumbecause any difficulty or bugs which may occur can be worked out with aminimum of disruption of the production line either by duplicatingstations or altering their location in the line or by changing theparticular tools at one or more stations simply by sliding out onepallet and substituting another. Once a production line for a particularproduct or article has been set up it is a simple matter to eitherremove it or to set up at a second later time when more articles must beproduced. This is accomplished by removing and storing the pallets 22with the tools and fixtures in place, for examples, in racks (not shown)from which the pallets can betaken and slid back into the supportingframes 20 when the production line is to be set up again. While thepallets 22 are stored, other pallets with different or similar tools andfixtures for performing a second series of operations are in thesupporting frames so that another article or device can be manufacturedand assembled.

The flexibility of my system is not limited to replaceable pallets 22,as the supporting frames, the service ducts 24, and belt conveyor 40 areall standard modular units built up as multiples of a single work centerhaving'one pallet work surface as described below. This makes itpossible to adapt the system to existing conditions and buildings and toalter the arrangement of the supporting frames 20 to accommodate adifferent type of manufacturing method or product.

The structural details of the frame 20 can best be seen in Figs. 3 to 5wherein two spaced horizontal angle mem bers 50 and 52 are of sufficientlength to accommodate two adjacent pallets 22. The adjustable legs forsupporting the angle members 50 and 52 each comprise a channel-shapedmember 54 the ends of whose flanges 56 (Fig. 5) are bent inwardly as toreentrant lips 58. At the lower end of the channel-shaped member 54 acover plate 60 is attached by cap screws 62 which pass through aperturesin the lips 58. The upper end of the channel member 54 is reenforced bya bracket 64 which is also channel-shaped so as to fit inside the end ofthe member.

The height of the pallet 22 is adjusted by means of a channel-shaped legextension 66 which telescopes into the bottom of the leg member 54. Thelower end of the extension 66 is closed by an end plate 67 havingapertured bosses 69 for securing the bench to the floor. The extension66 is secured in adjusted position by four bolts 68, two of which passthrough the front flange 56 of the leg member 54, the other two boltssimilarly passing through the rear leg. The bolts 68 also pass throughcorresponding slotted apertures in the flanges of the extension 66 toengage nuts 70 (Fig. 5).

The angle members 50 and 52 are attached to the top of the channelmembers 54 either directly, as at either end leg, by bolts 71 which passthrough the vertical flange of the respective angle member, the flangeof the adjacent channel member and the end of the stiffening bracket 64;or as at the center leg by means of a threehole strap 72 which issecured to the channel member 54 by a bolt 74 passing through its centerhole. Bolts 76 connect the strap 72 with the abutting ends of two anglemembers 52 (or 54). As can best be seen in Fig. 4, the rear angle member54 has a longer vertical flange than the front angle member 52 so thatthe pallet 22 can he slid under the rear angle member and rest upon thetop of the front angle member.

The service duct 24 at the rear of the work centers comprises achannel-shaped member 78 (Fig. 4) whose flanges have reentrant lips 80.The channel-shaped member 78 is formed in sections which are each aslong as two adjacent pallets 22 and is supported in place by bolting tothe rear angle member 54. To save valuable floor space the height of thechannel member 78 is preferably made at least several times itshorizontal width and the tubing and electrical conduits for the variousservices are installed by means of clamps (not shown), one above theother, as is best illustrated in Fig. 6 wherein one of the rear panels82 has been removed. The panels 82 are secured at their lower edge byclips 84 and at their upper edge by screws 86 which engage the channellips so that the panels are readily removable to allow the connectingand disconnecting of the flexible hoses from the Ts in the conduits suchas 87 (Fig. 6). The opposite ends of each row of work centers ispreferably finished by triangular end plates 88 secured to the end legsby cap screws 90.

The details of the conveyor 40 are shown in Figs. 7 to 9 wherein acontinuous belts 92 passes upon the opposite sides of the horizontal webof a supporting frame or guide 94 which has an I-shaped cross section asis best shown in Fig. 9. The belt guide 94 is made up of a plurality ofinterconnected elements each of which has a length equal to the width ofone pallet 22 so that the conveyor can be assembled to correspond to theoverall length of a row of any required number of work centers byjoining the required number of elements.

As is shown in Fig. 8, each guide element consists of a channel member96 arranged with its web portion in ahorizontal plane and its flangesextending downwardly. Welded respectively to the channel flanges are twoside pieces 98 whose width is greater than the width of the flanges sothat the upper edges of the side pieces extend up beyond the top of thechannel web. To give greater stiffness and stability to the guide 94 theside pieces 98 are offset or staggered with respect to the channelmember 96 of each guide element so that the projecting end of eachchannel is interposed between the side plates of the adjacent memberwhen in assembled position. The belt guide elements are maintained inassembled relationship by straps 100 which bridge the abutting ends ofthe side pieces 98 and are connected thereto by bolting.

The first and last frame elements are modified to receive the-belt motorM (Fig. 7) and the slack take-up device 102 (Fig. 8) respectively. Tothis end the side pieces 98' of the first frame element are extended theentire length of the channel and the projecting ends 5. notched, orrecessed. to journal a. shaft 104 carryinga belt roll (not shown). Theshaft 10.4 is connected with the speed reduction. unit of the. motor Mwhich, is supported upon a shelf 106 welded to. thebottom of the endguide element. The projecting. ends. of the side pieces 98. of the lastguide element are foreshortened and provided with horizontal slots toreceive the shaft of a take up roll- 108 (Fig. 8);. The; roll 102 isbiased outwardly by a spring 110.-wound around a rodof a clevis 112whose arms engage the shaft on either side. of the roll. The clevis rodis guided by an. aperture in a, plate 114 extending between the sideplates. 98", the. plate also acting as. the stationary seat for thespring 110.

The endless belt 92 is of such a length that it will pass around thedriven and take-up rolls and lie above and below the web of the: guide.channelmembers 96. Any slack is taken up bythe spring biased roll 108 sothat operation of the motor M causes the top of the belt 92'. to movepast the successive work centers and thus act as a conveyor. Tofacilitate the loading and unloading of articles from the conveyor,certain of. the side plates .98 are. notched at appropriate locations toaccommodate loading and. unloading chutes or ramps, 116 and 118. asshown in Fig. 9. The loading chute 1 16 consists of a channel memberwith its flanges extending. upwardly. One end of the channel is insertedin the notch in the side piece 98.. and its other end is raised by anupright 120 so. that any article deposited on. the channel slidesdownwardly onto the belt'92. The unloading chute is also formed of anupwardly facing channel with one end inserted in, a notch in the sidepiece 98; from which the chute inclines downwardly away from the belt92. To cause an article being carried by the belt 92 to be depositedupon the chute, the further flange of the chute channel is carriedarcuately across the belt in a direction opposed to the travel of thebelt to engage the opposite side piece 98 so that an article carried bythe belt engages the arcuate flange portion and is forced onto the chutedown along which the article slides to a box or work surface.

In Fig. 13 are shown several article containers or hoppers 38 and 38'arranged in a semi-circle on the top of a pallet 22 at a work centerwhich is being used to assemble the components held in the containers.It will be noted that because of their compactness and the smallsupporting area required, the containers can be conveniently grouped soas to save waste motion on the part of the operator.

As can be seen in Figs. and 11, each container 38 comprises a channelmember 122 whose web and flanges form three sides of a rectilinearhousing. The fourth side 124 of the housing is slidable in grooves 126formed adjacent the reentrant edges of the flanges of the channel member122. The top of the housing is covered by a cap 128 and the bottom by adeclivous bottom piece 130 which extends angularly upward from the lowerend of the slidable wall 124 to an intermediate location upon theopposed wall formed by the web of the channel 122 so that lifting of themovable wall permits the articles stored in the container to flowdownwardly and outwardly under the influence of gravity when the housingis in an upright position.

To facilitate the discharge of articles from the container 38 a mountingfoot 132 (Fig. 12) is screwed or otherwise permanently fastened to thepallet 22 or other work surface. The foot 132 has a declivous portion134 which is proportioned so as to insert in the cavity formed beneaththe bottom piece 130 and abut such piece when the container is loweredonto the foot. Formed integrally with the declivious portion 134 is achannel-shaped chute 136 whose flanges 138 converge to direct articlesdischarged from the container into a depression 140 in the channel webportion from which the articles can be readily taken by an operator.

A window for visually checking the number of components in the containeris provided, preferably by making the entire movable wall 124 of atransparent material such as glass, but it is to be understood that awindow could also be obtained by making all or part of any of the wallsof a transparent or translucent material. To facilitate such a check,indicia marks 142 (Fig. 10) which are related to the normal hourly ordaily rate of an operator are marked on the reentrant edge of the flangeof the channel member 122. A holder 143 for a card bearing identifyingdata is attached to the front of the container.

Fig. 14 diagrammatically illustrates the manner in which the containers38- facilitate the distribution of components to various work centers.Tote boxes 144 are provided which are proportioned to receive eight orten containers. The tote boxes 144 in turn slide into a stock room rack146 in a manner similar to a drawer. The stock room attendants fill thecomponent containers 146 at any convenient time and store the loadedcontainers in tote boxes 144 placed in the rack, 146. Whenevercomponents are required at. the production line a. tote box 144 iswithdrawn and carried or transported to the appropriate work center. Atthe work center the container 38 is taken from the tote box 144 anddropped on the mounting foot 132 at the work center. As the containerdescends onto the foot 132 the tops of the flanges 138 engage the bottomof the movable wall 124 so that the wall is slid upwardly and thecomponents descend down the chute 136 to the depression where they arepicked up by the operator.

it should be understood that the present disclosure is for the purposeo-fillustration. only and that this invention includes all modificationsand equivalents which fall within the scope of the appended claims.

I claim:

1. A manufacturing setup for the carrying out of a multiplicity ofrelated operations comprising a plurality of rectilinear pallets havingsubstantially the same dimensions, each of said pallets forming arespective work station and holding the tools used at the correspondingstation; and one or more supporting frames for said pallets eachincluding a pair of horizontal side members spaced to accommodate thewidth of said pallets and adapted to be aligned with the correspondingside members of the adjacent frames, the length of the side membersbeing an integral multiple of the length of the pallets so that themembers support the pallets in abutting end to end relationship, achannel member of substantially the same length as the rear side memberattached respectively to each thereof with its web vertically disposedadjacent the rear sides of the pallets to form a backing therefor and apanel interposed between the flanges of the channel member to form arectangular duct for the lines furnishing services, such as power, lightand compressed air, to the tools carried by the pallets at the variousstations.

2. A manufacturing setup according to claim 1 wherein the side membersare of angular cross section, one leg of each of which is verticallydisposed, the other legs being turned inwardly towards each other toform two spaced horizontal bearing surfaces upon which the pallets rest.

3. A manufacturing setup according to claim 1 wherein the supportinglegs each comprise a vertically disposed channel whose web isapproximately the same width as that of the pallets, a second channeltelescoping within the first channel and means for adjustably securingthe channels in their telescoped relationship whereby the height of theframe is variable.

4. A manufacturing setup according to claim 3 wherein the securing meansfor the channels include a plurality of fasteners with shanks which passthrough the abutting flanges of the channels.

5. A manufacturing setup including a plurality of work station supportsand a conveyor system for transporting articles to be manufactured atsaid plurality of work station supports comprising a belt conveyorincluding a plurality of elongated guide elements which areinterconnected in end to end relationship, the guide elements have anI-shaped cross section, a continuous belt which runs on each side of theweb of the I-shaped section lengthwise of the interconnected guideelements, a roller journaled respectively at each of the extremities ofthe interconnected guide elements about which the belt passes, powermeans for rotating one of the rollers to move the belt, and a supportingframe including a plurality of pairs of aligned horizontal side membersbetween which the work station supports are located, each of the frontside members being of approximately the same length and having acorresponding guide element attached thereto whereby the belt movesadjacent the work station supports.

6. A manufacturing setup according to claim wherein each conveyor guideelement includes a channel member arranged with its flanges extendingdownwardly from its Web, and two side members attached to the respectiveflanges of the channel, the flanges extending upwardly beyond the top ofthe web so that the cross section of the conveyor is I-shaped.

7. A manufacturing setup according to claim 6 wherein the side pieceshave the same length as the channel member but are longitudinally olfsetwith respect thereto so that the abutting joints of adjacent channelmembers are staggered with respect to the abutting joints of adjacentside pieces.

8. A manufacturing setup according to claim 6 wherein one or more of theside pieces are notched to accommodate loading and unloading ramps.

9. A manufacturing setup according to claim 6 wherein the loading rampcomprises a channel member arranged with its flanges extending upwardlywith one end engaging the notch in the side piece, the member beingtilted downwardly toward its notch engaging end so an article placedthereupon will slide onto the conveyor belt.

10. A manufacturing setup according to claim 6 wherein the unloadingramp comprises a channel member arranged with its flanges extendingupwardly with one end engaging the notch in the side piece, and atransverse piece is provided which extends between the opposed sidepieces adjacent the notch and immediately above the belt so that itshunts articles traveling upon the belt onto the ramp, the channelmember being tilted downwardly from its notch engaging end so thatarticles shunted thereon will slide down the ramp away from the belt.

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